Preface: I have some pretty strong opinions on this topic, so don't take anything the wrong way. We all know that sometimes fish die and that's that. What I say below is just my opinion based on experience. It's not scientific or anything, just my experiences.

There are a number of keys in my opinion to keeping fish alive. It starts the minute that you catch the fish.

In a Bass-n-Tubes tournament, the odds of culling a 3lb fish is about 1 in 1000. So anything over 3lbs, I never put a bouy in. Get the fish and put it directly in the livewell. It's out of the water may 30 seconds tops.

If it's a small fish I think I may cull later, I put a bouy in it. I sharpen the tips of the metal clips on all my bouys so that the hole is clean and easy, barely worse than a hook hole. Popping a jagged hole in the fishs' lip with a dull metal hook can't be good for the fish.

I use 'fish drugs' in my case some stuff called Please Release Me. I don't put in a ton, just a tablespoon's worth every few hours.

I use two pumps and I run them every 15 to 30 minutes for about 5 minutes at a time. I haven't found a need to run them continuously ever, but I suppose if it was really hot, that would be good.

If I have to pull a fish out of the livewell using the bouy, I grab the bouy in one hand and follow the line to the fish's mouth and then lip it in the water and pull it out. I try to avoid lifting up the fish using the bouy since if you clip on the top half of the mouth, you're likely to rip a 2" gash in the lip of the fish.

The last thing to mention is livewell size. A 10lb fish is going to be between 23 and 26 inches long. You could have a long 8lber that was 25" or a short 10lber that was 23". The point is, you need a livewell that measures diagonally at least 25/26". A fish with it's tail curved in the livewell is going to get pretty hurt by the end of the day.

Overall, I think it's how you handle the fish with your hands and how you bouy them (or not bouy them) that affects their health more than anything. You can pour fresh water and fish drugs on a fish all day but if you already messed it up on it's way into the livewell, there ain't much point. The fish you get off the hook and into the livewell with minimal handling are going to be the fish that come out lively at the end of the day.